openstrategy.java

jfa2ce 源码帮助开发人员更好的理解运用

/*******************************************************************************
 * Copyright (c) 2000, 2006 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jface.util;

import org.eclipse.core.runtime.ListenerList;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.TableTree;
import org.eclipse.swt.custom.TableTreeItem;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableItem;
import org.eclipse.swt.widgets.Tree;
import org.eclipse.swt.widgets.TreeItem;
import org.eclipse.swt.widgets.Widget;

/**
 * Implementation of single-click and double-click strategies.
 * <p>
 * Usage:
 * <pre>
 *	OpenStrategy handler = new OpenStrategy(control);
 *	handler.addOpenListener(new IOpenEventListener() {
 *		public void handleOpen(SelectionEvent e) {
 *			... // code to handle the open event.
 *		}
 *	});
 * </pre>
 * </p>
 */
public class OpenStrategy {
    /** 
     * Default behavior. Double click to open the item.
     */
    public static final int DOUBLE_CLICK = 0;

    /** 
     * Single click will open the item.
     */
    public static final int SINGLE_CLICK = 1;

    /** 
     * Hover will select the item.
     */
    public static final int SELECT_ON_HOVER = 1 << 1;

    /**
     * Open item when using arrow keys
     */
    public static final int ARROW_KEYS_OPEN = 1 << 2;

    /** A single click will generate
     * an open event but key arrows will not do anything.
     * 
     * @deprecated
     */
    public static final int NO_TIMER = SINGLE_CLICK;

    /** A single click will generate an open
     * event and key arrows will generate an open event after a
     * small time.
     * 
     * @deprecated
     */
    public static final int FILE_EXPLORER = SINGLE_CLICK | ARROW_KEYS_OPEN;

    /** Pointing to an item will change the selection
     * and a single click will gererate an open event
     * 
     * @deprecated
     */
    public static final int ACTIVE_DESKTOP = SINGLE_CLICK | SELECT_ON_HOVER;

    // Time used in FILE_EXPLORER and ACTIVE_DESKTOP
    private static final int TIME = 500;

    /* SINGLE_CLICK or DOUBLE_CLICK;
     * In case of SINGLE_CLICK, the bits SELECT_ON_HOVER and ARROW_KEYS_OPEN
     * my be set as well. */
    private static int CURRENT_METHOD = DOUBLE_CLICK;

    private Listener eventHandler;

    private ListenerList openEventListeners = new ListenerList();

    private ListenerList selectionEventListeners = new ListenerList();

    private ListenerList postSelectionEventListeners = new ListenerList();

    public OpenStrategy(Control control) {
        initializeHandler(control.getDisplay());
        addListener(control);
    }

    /**
     * Adds an IOpenEventListener to the collection of openEventListeners
     */
    public void addOpenListener(IOpenEventListener listener) {
        openEventListeners.add(listener);
    }

    /**
     * Removes an IOpenEventListener to the collection of openEventListeners
     */
    public void removeOpenListener(IOpenEventListener listener) {
        openEventListeners.remove(listener);
    }

    /**
     * Adds an SelectionListener to the collection of selectionEventListeners
     */
    public void addSelectionListener(SelectionListener listener) {
        selectionEventListeners.add(listener);
    }

    /**
     * Removes an SelectionListener to the collection of selectionEventListeners
     */
    public void removeSelectionListener(SelectionListener listener) {
        selectionEventListeners.remove(listener);
    }

    /**
     * Adds an SelectionListener to the collection of selectionEventListeners
     */
    public void addPostSelectionListener(SelectionListener listener) {
        postSelectionEventListeners.add(listener);
    }

    /**
     * Removes an SelectionListener to the collection of selectionEventListeners
     */
    public void removePostSelectionListener(SelectionListener listener) {
        postSelectionEventListeners.remove(listener);
    }

    /**
     * Returns the current used single/double-click method
     * 
     * This method is internal to the framework; it should not be implemented outside
     * the framework.
     */
    public static int getOpenMethod() {
        return CURRENT_METHOD;
    }

    /**
     * Set the current used single/double-click method.
     * 
     * This method is internal to the framework; it should not be implemented outside
     * the framework.
     */
    public static void setOpenMethod(int method) {
        if (method == DOUBLE_CLICK) {
            CURRENT_METHOD = method;
            return;
        }
        if ((method & SINGLE_CLICK) == 0) {
			throw new IllegalArgumentException("Invalid open mode"); //$NON-NLS-1$
		}
        if ((method & (SINGLE_CLICK | SELECT_ON_HOVER | ARROW_KEYS_OPEN)) == 0) {
			throw new IllegalArgumentException("Invalid open mode"); //$NON-NLS-1$
		}
        CURRENT_METHOD = method;
    }

    /**
     * Return true if editors should be activated when opened.
     */
    public static boolean activateOnOpen() {
        return getOpenMethod() == DOUBLE_CLICK;
    }

    /*
     * Adds all needed listener to the control in order to implement
     * single-click/double-click strategies.
     */
    private void addListener(Control c) {
        c.addListener(SWT.MouseEnter, eventHandler);
        c.addListener(SWT.MouseExit, eventHandler);
        c.addListener(SWT.MouseMove, eventHandler);
        c.addListener(SWT.MouseDown, eventHandler);
        c.addListener(SWT.MouseUp, eventHandler);
        c.addListener(SWT.KeyDown, eventHandler);
        c.addListener(SWT.Selection, eventHandler);
        c.addListener(SWT.DefaultSelection, eventHandler);
        c.addListener(SWT.Collapse, eventHandler);
        c.addListener(SWT.Expand, eventHandler);
    }

    /*
     * Fire the selection event to all selectionEventListeners
     */
    private void fireSelectionEvent(SelectionEvent e) {
        if (e.item != null && e.item.isDisposed()) {
			return;
		}
        Object l[] = selectionEventListeners.getListeners();
        for (int i = 0; i < l.length; i++) {
            ((SelectionListener) l[i]).widgetSelected(e);
        }
    }

    /*
     * Fire the default selection event to all selectionEventListeners
     */
    private void fireDefaultSelectionEvent(SelectionEvent e) {
        Object l[] = selectionEventListeners.getListeners();
        for (int i = 0; i < l.length; i++) {
            ((SelectionListener) l[i]).widgetDefaultSelected(e);
        }
    }

    /*
     * Fire the post selection event to all postSelectionEventListeners
     */
    private void firePostSelectionEvent(SelectionEvent e) {
        if (e.item != null && e.item.isDisposed()) {
			return;
		}
        Object l[] = postSelectionEventListeners.getListeners();